Irrigation water discharge valve

ABSTRACT

A water discharge valve designed to be coupled by means of an automated irrigation system. The water discharge valve comprises an enlargement having spherical surfaces at the upper end of a vertical riser and housing a ball that opens or closes the valve in response to the water or in response to an actuating member mounted on the movable irrigation system.

RELATED APPLICATIONS

This is a division of co-pending patent application Ser. No. 711,986,which was filed Aug. 5, 1976, now U.S. Pat. No. 4,159,080 and is titled"Irrigation Apparatus".

BACKGROUND OF THE INVENTION

The present irrigation apparatus is designed to automate sprinkling of afield by use of a wheel-supported lateral pipeline having a plurality ofsprinklers spaced along a center pipeline axis. A lateral pipeline isselectively supplied with water from a stationary water supply linehaving a plurality of water discharge valves spaced along its length.The apparatus is alternately in a stationary mode adapted to behydraulically coupled to the water supply line through a selected waterdischarge valve, or in a traveling mode uncoupled from the water supplyline and with the lateral pipeline powered for movement in a directionparallel to the supply line. The novel combination comprises a carriageguided along the water supply line, a structural fluid connectionbetween the lateral pipeline and the carriage and sensing means forindexing the carriage by reference to a selected water discharge valve.A valve actuator on the carriage completes a hydraulic circuit from thewater supply line to the lateral pipeline through the structural fluidconnection. The entire apparatus is controlled sequentially from thecarriage.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic plan view of a wheel move irrigation systemaccording to this disclosure;

FIG. 2 is a fragmentary end view from the left in FIG. 1;

FIG. 3 is an elevation view of the elements shown in FIG. 2;

FIG. 4 is an enlarged view of the carriage as seen from the right inFIG. 2, with portions of some elements being broken away;

FIG. 5 is a sectional view taken along line 5--5 in FIG. 4, with thevalve actuator in its open position and clear of a riser;

FIG. 6 is a sectional view taken along line 6--6 in FIG. 4;

FIG. 7 is a schematized view similar to view 6, showing release of ariser;

FIG. 8 is a schematized view similar to FIG. 6, showing the normaltravel position;

FIG. 9 is an enlarged fragmentary view taken along line 9--9 in FIG. 8;

FIGS. 10, 11 and 12 are fragmentary plan views showing operation of thestop bolt;

FIG. 13 is an enlarged fragmentary sectional view taken along line13--13 in FIG. 1;

FIG. 14 is a schematic view of the electrical controls; and

FIG. 15 is a schematic view of the hydraulic controls.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

General Arrangement: The present invention is illustrated as it appliesto automation of wheel move irrigation systems. A typical wheel moveirrigation system to which the invention might be applied is illustratedin FIG. 1. A lateral pipeline 10 extends across the transverse width ofthe field to be irrigated. The lateral pipeline 10 is adapted to bemoved from one end of the field to the other in a directionperpendicular to the width of the field as measured across the length ofpipeline 10. To accomplish such movement, the pipeline 10 has aplurality of spaced wheels 11 mounted to it. Wheels 11 are typicallyfixed to pipeline 10 in a coaxial arrangement. The pipeline 10, which isthe water conduit across the field, also serves as the driving axle forwheels 11 and is commonly referred to as a "torque tube". A plurality ofsprinklers 12 are spaced along the center axis of pipeline 10 todischarge water onto the field in a desired pattern while the lateralpipeline is stationary. Sprinklers 72 are typically fixed to pipeline 10and rotate with its as it is moved from place to place. Alternate typesof sprinklers might be used along draglines extending rearwardly frompipeline 10 or on rotatable mounts so that they remain upright duringrotation of pipeline 10.

The lateral pipeline 10 is driven by a prime mover 13. This essentiallycomprises a frame extending to one or both sides of the pipeline 10 andterminating in ground-engaging wheels at its outer ends that serve asreaction members to counter the torque applied to rotate pipeline 10about its center axis. The prime mover 13 is typically provided with agasoline powered motor coupled to the pipeline 10 by a reversibletransmission, or a clutch or drive sprockets and chains. The motorprovides a low speed, high torque rotational force applied to thelateral pipeline 10 to turn about its center axis. Prime mover 13 isusually centered along pipeline 10, the pipeline then serving totransmit this rotational force outward along its length to the wheels11.

The pipeline 10 is typically provided with water from a stationary watersupply line 14 oriented along the length of the field perpendicular tothe pipeline 10. Line 14 can be above ground or below ground. The watersupply line 14 is arranged parallel to the intended direction ofmovement of the lateral pipeline 10, although the precise movement ofpipeline 10 in practice in seldom exactly parallel to the water supplyline 14 because of ground surface variations. Also, the substantiallength of a lateral pipeline results in rotational "winding" of thepipeline from each end to the center, causing variations in the movementof the wheels spaced along its length.

The water supply line 14 is provided with a plurality of water dischargevalves 15 on vertical risers spaced along its length. They are typicallyspaced apart by a distance equal to the normal spacing between theprearranged settings of lateral pipeline 10 along the length of thefield.

In a conventional manual operation, the pipeline 10 is moved by manualoperation of prime mover 13, which rotates the pipeline 10 and wheels 11to transport pipeline 10 from one setting to the next. At each settingthe inlet end of pipeline 10 is manually connected to the adjacent waterdischarge valve 15, which is then manually operated to supply water tothe sprinklers 12 while the pipeline 10 is stationary. This typicallyrequires manual movement of the pipeline 10 every few hours. Thesubstantial amount of manual labor involved in utilizing wheel moveirrigation systems is a detrimental factor and has led the irrigationindustry away from this pioneering type of irrigation system to muchmore complicated and expensive continuously moving lateral sprinklersand center pivot sprinkler irrigation systems.

As can be seen in FIGS. 1 through 3, the present improvement provides anautomated carriage 20 which travels along the water supply line 14 inunison with movement of lateral pipeline 10 in a direction parallel tothe length of water supply line 14. Carriage 20 is operatively connectedto lateral pipeline 10 by means of a structural fluid conduit 16, whichis rotatably journalled by pipeline 10 during travel along a field.Automatic sensing means is provided on carriage 20 for indexing purposesto locate its position with respect to each water discharge valve 15. Avalve actuator means is provided on carriage 20 to automatically coupleand disconnect the fluid conduit 16 to a selected valve 15.

Controls are provided on carriage 20 for all functions required toautomate movement of prime mover 13 and to synchronize such functionswith operation of the devices mounted on carriage 20. Carriage 20automatically controls operation of the lateral pipeline 10 between astationary mode wherein it is hydraulically coupled to the water supplyline 14 through a selected water discharge valve 15 or an alternatetraveling mode wherein the lateral pipeline 10 is powered by prime mover13 for movement along the length of the field in a direction parallel tothe length of water supply line 14.

Water Discharge Valve: FIGS. 4 and 5 illustrate details of a specialwater discharge valve mounted along water supply line 14 andparticularly adaptable to the automated control and operationalsequences described below.

Water discharge valve 15 is mounted at the upper end of a vertical riser17 that is in open communication with the supply line 14. The height ofthe riser 17 is immaterial, but will normally be substantially uniformalong the length of a given water supply line 14, whether line 14 isabove or below ground level. In the case of a buried or below groundwater supply line 14, there might be variations in the heights of risers17 above the ground surface. An alternate carriage support toaccommodate such variations is disclosed below.

At the upper end of each riser 17 is a spherical enlargement 18 havinginterior and exterior spherical surfaces. The open rim at the upper endof the enlargement 18 is circular and is of a diameter less than thespherical diameter of a ball 19 located within the enlargement 18. Ball19 is preferably made of material that floats in water, its buoyancybeing utilized in conjunction with the water pressure within supply line14 to normally maintain ball 19 in a closed or sealed position at theupper end of the spherical enlargement 18. As a typical example, ball 19can be machined of wood and covered with a suitable resilient plasticresin capable of sealing engagement against the interior walls of thespherical enlargement 18 without permanent deformation. The illustratedvalve 15 is therefore normally maintained in a closed condition by thewater pressure within supply line 14. It can be opened by physicallymoving ball 19 in a vertical downward direction to center it within thespherical enlargement 18. This concentric spherical configurationresults in a minimum of hydraulic restriction through the riser.

Connecting Fluid Conduit: Fluid conduit 16 basically comprises astructural fluid connection mounted between the inlet of lateralpipeline 10 and carriage 20 for permitting elevational and lateralmovement of the inlet of pipeline 10 relative to the carriage 20 whileimparting translational movement to the carriage 20 in a directionparallel to the length of the water supply line 14 in unison withmovement imparted to the lateral pipeline 10 in a direction parallel tothe length of water supply line 14 while the lateral pipeline 10 is inits traveling mode. As shown in FIGS. 1, 2 and 13, it comprises ahorizontal extension 58 and a perpendicular coupler drop 60 leading tothe flanged outboard end of fluid conduit 16 described below withrespect to the details of carriage 20.

The horizontal extension 58 is shown as having a diameter less than theinterior diameter of the lateral pipeline 10, and is telescoped withinthe open outer end of pipeline 10 for free movement parallel to the axisof pipeline 10 when the sprinkler apparatus is in its traveling mode.The fluid conduit 16 is at the same time also freely rotatable withrespect to lateral pipeline 10 so that the pipeline 10 can roll duringmovement along the field without rotating the depending coupler drop 60and carriage 20. To accomplish this, an expandable water seal 61 and asuitable outer bushing 59 rotatably mount horizontal extension 58 withinthe interior of the lateral pipeline 10 (FIG. 13).

While the seal 61 automatically expands to engage the interior oflateral pipeline 10 when the pipeline 10 is provided with water underpressure, it does not adequately resist axial movement of pipeline 10with respect to the coaxial horizontal extension 58 of the fluid conduit16 due to interior water pressure. To secure the horizontal extension 58within pipeline 10 against such axial movement when the irrigationapparatus is in its stationary mode for sprinkling purposes, there isprovided a circumferential bladder 62 wrapped about the horizontalextension 58 adjacent to its inner end. The horizontal extension 58 isperforated about the interior of bladder 62 so as to permit water underpressure within horizontal extension 58 to flow through bladder 62 andexpand it against the interior circumference of pipeline 10 to provide asubstantial area of engagement to frictionally resist any movementbetween lateral pipeline 10 and the horizontal extension 58.

It is to be noted that the operation of the seal 61 and bladder 62 bothdepend upon interior water pressure and are therefore an automaticfunction of the pressurization of lateral pipeline 10. They assure thatthere will be no further relative movement between the fluid conduit 16and lateral pipeline 10 during the time in which the conduit 16 iscoupled to a stationary riser 17 and there is hydraulic communicationfrom the selected water discharge valve 15 and the sprinklers along thelateral pipeline 10. They assure free relative motion in the absence ofwater pressure.

Carriage: Carriage 20 is illustrated in detail in FIGS. 4 through 8, andis generally shown in FIGS. 2 and 3. It comprises a rigid frameworkincluding two horizontal base plates 21 which straddle the risers 17 ateach side as carriage 20 moves along the length of water supply line 14.Base plates 21 are connected to one another by a rigid transverse arch22 which is welded or suitably fixed across corresponding ends of theplates 21. The opposite ends of base plates 21 support a pair of uprightrigid hollow tanks 23 connected by a transverse upper brace 24. Botharch 22 and brace 24 are vertically positioned on carriage 20 to clearthe upper end of each riser 17 encountered along water supply line 14. Astationary actuator housing 25 is centered across carriage 20 by a pairof guide rods 26. Guide rods 26 are fixed between bosses fixed to thehousing 25 and base plates 21. The stationary guide rods 26 are mountedin vertical upright positions parallel to one another at the respectivesides of the carriage framework.

Guide means are operatively mounted between the carriage 20 and watersupply line 14. The purpose of the guide means is to maintain the pathof movement of the carriage parallel to the length of the line 14. Thiscan be accomplished by reference to either the water supply line 14 orthe risers 17. In the preferred embodiment illustrated in FIGS. 2through 8, guide wheels 27 are used for this guiding purpose. Guidewheels 27 mounted to the lower ends of guide rods 26 tangentially engagethe water supply line 14 at opposite sides of its center axis and serveas rolling guides to maintain proper spatial positioning of carriage 20as it moves along the length of water supply line 14.

Carriage 20 is provided with sensing means to detect the presence ofeach riser 17 as the carriage moves along water supply line 14 and toindex the location of carriage 20 along the length of line 14 inpreparation for actuation of a referenced water discharge valve 16 andsubsequent hydraulic control through conduit 16. This sensingarrangement is best illustrated in the operational sequence shown inFIGS. 6, 7 and 8.

The sensing means comprises a mechanical escapement that accuratelygrasps or cradles each riser at opposite sides of its circumference. Itis designed to locate and engage a riser 17 during movement of carriage20 along supply line 14 in either direction. While FIGS. 6, 7 and 8 aredrawn to illustrate the sequential operation of the sensing means whencarriage 20 is being moved along line 14 in the direction shown by arrow29, it is to be understood that an identical sequence of events willoccur should carriage 20 engage a riser 17 while moving in the oppositedirection.

Engagement of riser 17 is accomplished by two cam plates 28, 30pivotally mounted about the respective guide rods 26 at the oppositesides of carriage 20. Each cam plate 28, 30 is free to pivot about theaxis of the rod 26 on which it is mounted. The cam plates 28, 30 arearranged in a horizontal position perpendicular to guide rods 26. Whennot in engagement with a riser 17, they are centered in alignment withone another across the carriage 20 in the positions shown in FIG. 8.They are yieldably maintained in these positions by opposed centeringtension springs 33. While cam plates 28, 30 are free to pivot about theaxes of guide rods 26 as influenced by engagement with a riser 17, theyare yieldably urged to their central or neutral position shown in FIG. 8by the centering springs 33.

Complementary circular cam surfaces 31, 32 are formed across therespective cam plates 28, 30 above the water supply line 14. Thecircular cam surfaces 31, 32 are formed to a diameter slightly largerthan the outer cylindrical diameter of the risers 17. They are spacedoutward from the axes of guide rods 26 by a distance permittingcomplementary circumferential engagement of each riser 17 by the camplates 28, 30 when the riser 17 is indexed in transverse alignmentbetween the guide rods 26 (FIG. 6).

As illustrated, one cam plate 28 extends outward from its supportingguide rod 26 a distance greater than does the remaining cam plate 30.The distance illustrated is such that the engagement between riser 17and cam surface 31 will extend to the center line of water supply line14 when a riser 17 is centered between guide rods 25. This providesmaximum longitudinal contact across the surface of riser 17 tophysically oppose continued movement of carriage 20 in the directionshown by arrow 29.

Carriage 20 is designed to mechanically prevent its continued movementpast the operational position shown in FIG. 6 until the controlsassociated with it have completed all functions required while thelateral pipeline 10 is in its stationary mode.

To mechanically or physically prohibit such further movement, a movablestop bolt 35 is mounted through base plate 21 beneath the back side ofcam plate 28. The solid stop bolt 35 has a substantial diameter and isspring mounted so as to be yieldably urged to an upwardly protrudingposition with respect to base plate 21 wherein it intersects theoperational plane of cam plate 28. Its raised or upper position isillustrated in full lines in FIG. 9. The back side of cam plate 28 hascomplementary shoulders 34 spaced arcuately about the axis of the guiderods 26 to physically abut stop bolt 35. Since abutment of shoulder 34by stop bolt 35 physically prevents further pivotal movement of camplate 28 about its supporting guide rod 26, the carriage 20 is therebyprevented from any continued movement along the length of water supplyline 14 until the stop bolt 35 is moved to the retracted or lowerposition shown in dashed lines in FIG. 9.

The arcuate cam plates 28, 30 are mounted to carriage 20 to sense thepresence of a riser 17 and physically center it in a predeterminedindexed location with respect to the movable carriage 20. The flangedoutboard end of fluid conduit 16, which is movably mounted to carriage20, is then properly centered above the selected riser 17 for couplingand engagement to the water discharge valve 15.

The outboard end of fluid conduit 16 is bent to present a downwardlyfacing vertical opening that is flanged at 36. The interior of flange 36is complementary to the exterior spherical configuration of theenlargement 18 at the upper end of riser 17. A circular gasket 37 isfixed across the opening presented by flange 36 to provide a pressureseal between the spherical enlargement 18 and the flange 36. Theoutboard end of fluid conduit 16 is vertically movable from a closedposition, wherein it engages a selected water discharge valve 15centered by the cam plates 28, and 30 and completes a hydraulic circuitfrom the water supply line 14 to the lateral pipeline 10, and an openposition vertically clear of the water discharge valve 15 to accommodatemovement of carriage 20. The closed position is illustrated by FIG. 4and the open position is illustrated by FIG. 5.

An actuator rod 38 extends downwardly from the center of the stationaryactuator housing 25 and into the interior of the fluid conduit 16coaxial with the opening at flange 36. Actuator rod 38 is fixed to thefluid conduit 16 by a locking screw 42 received through a guide boss 41on the exterior of the fluid conduit 16.

The actuator housing 25 illustrated in the drawings is a typicalpneumatic brake cylinder used in the trucking industry. It basicallycomprises a transverse movable diaphragm 50 which is yieldably urged byspring 39, to a raised position (FIG. 5), but which is movabledownwardly under hydraulic or pneumatic pressure to a lowered position(FIG. 4).

The lower end of actuator rod 38 has a downwardly facing enlarged cup 40fixed at its outer end. Cup 40 has a lower concave surface adapted toengage the upper portion of ball 19 within riser 17 so as to push theball 19 downwardly in opposition to the water pressure. The elevationalposition of cup 40 relative to flange 36 is such that flange 36 andgasket 37 will form an initial hydraulic seal against sphericalenlargement 18 before the cup 40 engages and moves ball 19 to completethe hydraulic circuit from the water supply line 14 to the fluid conduit16.

The lower end of fluid conduit 16 is guided by a pair of bearings 52mounted to it at opposite sides of the carriage 20. The bearings 52 areslidably guided on the guide rods 26 to assure proper vertical movementof the outboard end of fluid conduit 16 with respect to the framework ofcarriage 20. This guide arrangement assures that the actuator rod 38will remain parallel to the fixed guide rods 26 to permit propermovement of the fluid conduit 16 without binding.

As can be seen in FIG. 4, an actuator pin 51 is mounted outward from thebearing 52 above cam plate 28 on a projecting bracket 52. The verticalaxis along the center of pin 51 is coaxial with the vertical axis ofstop bolt 35. Pin 51 moves upwardly and downwardly relative to theframework of carriage 20 in unison with the outboard end of fluidconduit 16. It is slidably guided within bracket 59 and is urgeddownward by a compression spring 53 having sufficient force to move stopbolt 35 to its lower or retracted position. Spring 53 permitsover-travel of bracket 59 so as to assure proper retraction of stop bolt35 each time that the outboard end of fluid conduit 16 is seated on thespherical enlargement 18 of a riser 17.

As can be seen in FIG. 4, the described arrangement provides a positiveclamping pressure across the top of riser 17. Because of theinterconnecting carriage framework, and particularly the mounting of theactuator housing 25 and cam plates 28, 30 on the common guide rods 26,there is a direct vertical application of force in an upward directionbetween the cam surfaces 31, 32 and the lower partial circumference ofspherical enlargement 18 and the flange 36 and an equal opposingdownward force applied between the flange 36 and the upper circumferenceabout the opening of spherical enlargement 18. This assures a properhigh pressure hydraulic seal for efficient transfer of water between thestationary riser 17 and the movable fluid conduit 16. When the valveactuator assembly is operative in the closed position, the carriage 20is actually slightly lifted relative to the water supply line 14 and theguide wheels 27 can disengage from contact with the line 14.

In order to permit the cam plate 28 to pivot beyond the position shownin FIG. 6 to permit passage of carriage 20 past the indexed riser 17,there is provided a stop bolt retaining plate 54 immediately beneath thecam plate 28. Stop bolt retaining plate 54 is parallel to cam plate 28and is also pivotally mounted on the guide rod 26 that mounts cam plate28. Its back side is provided with two slotted lugs 57 which arecomplementary to an upwardly protruding pin 55 formed at the uppersurface of stop bolt 35. The plate 54 is freely pivotable about the axisof the guide rod 26 which supports it. It is moved by a yieldableconnection to the cam plate 28. This yieldable connection is shown as alight tension spring between the outermost end of cam plate 28 and thecenter of plate 54 facing toward the opposite side of carriage 20.Spring 56 is visible in FIG. 4 and is illustrated in dashed lines inFIGS. 6 and 7. The operation of plate 54 is illustrated in FIGS. 10, 11and 12.

As cam plate 28 moves to one side or the other, the retaining plate 54will be urged in the same direction of pivotal movement. It first abutsthe stop bolt 35 and prevents further pivotal movement of retainingplate 54 under the continuing tension force applied through the spring56 on the moving cam plate 28 (FIG. 10). However, when the stop bolt 35is retracted to the position shown in dashed lines in FIG. 9, theretaining plate 54 is then free to continue its pivotal movement untilthe intersecting pin 55 is abutted within the receiving slot of theengaged lug 57 (FIG. 11). In this condition, the stop bolt 35 ismaintained in its retracted position due to its engagement against thelower surface of the slotted lug 57. See FIG. 6. When carriage 20 isagain moved along the length of water supply line 14, the arcuate camplates 28, 30 are then free to pivot beyond the point of engagement ofshoulder 34 and stop bolt 35 to clear the riser 17 in the mannerillustrated in FIGS. 7 and 12. When riser 17 is cleared by both plates28, 30, they will return to their centered transverse positions shown inFIG. 8. At the same time, tension spring 56 will return the retainingplate to its centered condition. As soon as the slotted lug 57 clearsthe top of stop bolt 35, it will be automatically returned to its normalraised position shown in full lines in FIG. 9 and the entire sensingapparatus will have been reset in preparation for engagement with asubsequent riser.

Prime Mover Controls: FIG. 14 is a schematic view of a simple electricalcontrol for operating the prime mover 13 in a forward or reversedirection. In this simplified control, a motor control 63 is utilized inconjunction with a direct current power source 64, such as a storagebattery. The battery 64 can be mounted directly to the carriage 20,although the specific mounting is not shown in the remaining drawings.The mover control 63 is grounded at 65. It is designed to operate theprime mover in one direction of travel when the ground is positive andin an opposite direction of travel when the ground at 65 is negative. Itstops the movement of prime mover 13 when no current is supplied toground at 65. By utilizing the metal components of carriage 20, fluidconduit 16 and lateral pipeline 10 as a ground connection, the primemover 13 can be effectively controlled through an additional single wirebetween carriage 20 and motor control 63. The motor control 63 can be arelay control for an electric motor or can be an automatic control for agasoline engine. While many additional functions can be added to chokean engine, operate a clutch, etc., only the essential functions of theforward, reverse and stop controls will be described herein.

Battery 64 has its terminals connected to opposite sides of a doublepole, double throw switch 66 having a pivoted operating lever 67 movablebetween a forward position, a reverse position, and an open or stopposition. As shown, in the forward position the negative terminal ofbattery 64 is connected to the control line 68 to the motor control 63and the positive terminal of battery 64 is connected to ground at 70. Inits reverse position the switch 66 connects the positive terminal ofbattery 64 to line 68 and the negative terminal to ground at 70. In itsopen or neutral position, neither terminal of battery 64 is connected toeither line 68 or ground at 70 and therefore no power can be disipatedfrom battery 64.

The switch 66 is preferably mounted at the inboard side of the guide rod26 that pivotally supports the principal cam plate 28. As can be seen inFIG. 4, this locates all of the control components at one side ofcarriage 20. The lever 67 faces the risers 17 and can be contacted byprotruding tabs 71 fixed to selected risers 17.

Two differing lengths of tabs 71 can be selectively utilized to operatelever 67 as carriage 22 moves past a riser 17. A short extension wouldbe mounted to a riser 17 to pivot the lever 67 to its neutral positionand stop all further operation of the prime mover 13. Such a tab wouldbe mounted to an end riser where no further operation of the lateralpipeline 10 is desired after the carriage 20 reaches the selected riser.If it is desired that the lateral pipeline reverse itself, a longerextension on a tab 71 would be used to contact the lever 67 and pivot itto either the forward or reverse position, depending upon its initialdirection of travel. The longer extension of a tab 71 is shown in FIG.4.

Line 68 is connected in series to the normally closed contacts of amechanical drain timer 72. This timer 72 is mounted to carriage 20 andcan be seen in FIGS. 2 and 4. Line 68 also contains parallel switchesindicated by the reference numbers 73 and 74. Switch 73 is a stop boltsensor and can be seen in FIG. 9. It is mounted to the under side of thebase plate 21 adjacent to stop bolt 35. It is normally open when thestop bolt 35 is in its raised position and is closed when the stop bolt35 is in its retracted position.

Switch 74 is a stop switch and is operated by pivotal movement of camplate 28. As can be seen in FIGS. 6, 7 and 8, the switch 74 is fixed tothe upper surface of cam plate 28 and moves in unison with it about theguide rod 26. It is actuated by alternate lobes 75 fixed to the guiderod 26. Switch 74 is normally closed, and is opened when the riser 17 iscentered between the guide rods 26 (FIG. 6). It remains open while theriser 17 clears the engaging cam plate 28 (FIG. 7). It again closes whenthe cam plate 28 returns to its neutral transverse position (FIG. 8).

The stop bolt sensor 73 assures that line 68 is an open circuit so longas the stop bolt 35 is in its raised position, where stop bolt 35physically prevents further movement of carriage 20 due to the physicalabutment of riser 17, cam plate 28 and stop bolt 35. The stop switch 74serves to initially sense the presence of a riser 17 between the guiderods 26 of carriage 20 and opens the line 68 to terminate operation ofprime mover 13 when this position has been reached. Limit switches (notshown) may be mounted to the outer end of lateral pipeline 10 to detectextreme inward or outward movement of lateral pipeline 10 relative tothe horizontal extension 58 of fluid conduit 16. They would be in seriesin line 68. Should misalignment of lateral pipeline 10 result in axialmovement between pipeline 10 and the horizontal extension 58 beyond thephysical limits of the telescoping length of the horizontal extension58, one or the other of these switches would open to shut down theoperation of the prime mover 13 until the situation has been manuallycorrected.

Line 68 is electrically connected along the rotatable lateral pipeline10 by a conventional slip ring assembly 76 (FIG. 13) having a rotatablemember mounted on an insulator on pipeline 10 and a stationary membersimilarly mounted on horizontal extension 58 of fluid conduit 16. Acontinued ground contact is assured by a conductor 77 resilientlyconnected to pipeline 10 and maintained in contact with extension 58.The stationary member in slip ring assembly 76 may be prevented fromrotation by use of a pendulum (not shown).

Hydraulic Controls: FIG. 15 schematically illustrates the hydrauliccontrols that operate the movable diaphragm 50 and actuator rod 38 toselectively close or open the valve actuator assembly.

In the illustrated embodiment, the water under pressure within supplyline 14 is stored on carriage 20 and used to actuate the water dischargevalve 15. With the valve 15 operative for sprinkling as illustrated,water is supplied to the interior of the hollow tanks 23 through a bleedhose 78 including a check valve 80. The bleed hose 78 is tapped to theoutboard end of fluid conduit 16 upwardly adjacent to flange 36. Theinteriors of the two tanks 23 are in open hydraulic communicationthrough a connecting length of hose (not shown).

Operational control of the hydraulic elements is effected by a valve 82.Valve 82 moves between a first position wherein the interior of thetanks 23 is in hydraulic communication with the area above diaphragm 50within the stationary actuator housing 25, and a second position whereinthe area above diaphragm 50 is exhausted to atmosphere at 81 throughconnecting hose 83.

Valve 82 is moved to its first or operative position by a cam 85 fixedto the upper surface of the arcuate cam plate 28. A cam follower 86actuates valve 82 after cam plate 28 has pivoted to the position shownin FIG. 6 with the riser 17 centered between guide rods 26. When valve82 is activated, the hydraulic pressure within the tanks 23, which serveas accumulators, is directed to the interior of housing 25 to force theactuator rod 38 downwardly and operate the water discharge valve 15.While the water discharge valve 15 is activated, the hose 78 will directwater under pressure through check valve 80 to the interior of the tanks23 to recharge them.

A mechanical irrigation timer 87 mounted to carriage 20 serves tomechanically move valve 82 to its deactivated condition through alinkage shown at 88 (FIG. 6). It overrides cam 85 to allow valve 82 tomove down. This exhausts the pressure above diaphragm 50 and causes theactuator rod 38 to be lifted due to the biasing spring built into thediaphragm 50. This removes the source of water pressure from hose 78.The pressure is maintained within the charged tanks 23 due to thepresence of check valve 80 within the connections to hose 78.

Timer Controls: The illustrated apparatus uses two mechanical timers tocontrol the time during which the field is irrigated by sprinklers 12and the time between irrigating and moving the lateral pipeline 10,during which the pipeline 10 is drained automatically by conventionalvalves provided along its length. The irrigation timer 87 resets valve82 to drain the valve actuating device and terminate the connection offluid conduit 16 and the selected water discharge valve 15. The draintimer 72 closes the switch contacts in line 68 to begin operation of themotor control 63 after the time necessary to drain the pipeline 10.

Both timing units are mechanically set by pulleys and cables operated inresponse to movement of the outboard end of fluid conduit 16 along guiderods 26 (FIGS. 4, 6). Cable 107 sets irrigation timer 87 as the outboardend of fluid conduit 16 moves upwardly and releases timer 87 foroperation as it moves to its closed position. Cable 89 sets drain timer72 as the outboard end of fluid conduit 16 moves downwardly and releasestimer 87 for operation as it moves to its open position. Thisarrangement incorporates the use of conventional mechanical timers andit is to be understood that electronic timing circuits or time delaycircuits can be substituted if desired.

Sequence of Operation: The operational functions of the elementsincorporated in the apparatus have been described above. The followingwill simply capsule the sequence that occurs as the carriage 20 movesfrom riser to riser.

Assuming that carriage 20 is moving along water supply line 14 in thedirection shown by arrow 29 in FIGS. 6, 7 and 8, an operational cyclewill begin with contact of riser 17 by the complementary cam plates 28,30. This initial contact will instigate pivotal movement of the camplates 28, 30 in response to the continuing movement of carriage 20. Thecam plates 28, 30 act as detectors to sense the presence of riser 17.This is translated into an electrical signal by opening of stop switch74. This opens the circuit to the motor control 63 and stops thecontinued operation of prime mover 13. However, since the prime mover 13might continue to impart slight rolling movement to the lateral pipeline10, and the outer ends of lateral pipeline 10 might continue to rollslightly due to the resilient "winding" along its extreme length, theraised stop bolt 35 will be mechanically engaged by shoulder 34 tophysically interlock the carriage 20 to riser 17 in the location orindexed position shown in FIG. 6. The stop bolt 35 therefore physicallyprevents any further movement of carriage 20.

Just shortly after opening of switch 74, the rotary cam 85 will move thecam follower 86 to activate valve 82 to its raised position as shown inFIG. 15. This directs water under pressure from tanks 23 to the areaabove diaphragm 50 and initiates downward movement of actuator rod 38.As actuator rod 38 begins to move downwardly, the cable 89 starts to setthe drain timer 72. This immediately opens the drain timer contactsshown at 72 in FIG. 14, which maintains the circuit to the motor control63 in an open condition throughout the remainder of the time in whichcarriage 20 is in its stationary mode.

As the actuator rod 38 moves downwardly, the gaskets 37 will form a sealabout the exterior of the spherical enlargement 18, completed bypositive pressure between the enlarged flange 36 at the outboard end offluid conduit 16, which clamps against the enlargement 18 in oppositionto the engagement of enlargement 18 by the cam surfaces 31, 32 on thecam plates 28, 30. As soon as that seal is complete, the cup 40 at thelower end of actuator rod 38 moves the ball 19 to its open position(FIG. 4). During the downward movement of actuator rod 38, pin 55engages stop bolt 35 and pushes it to the retracted position shown indashed lines in FIG. 9. It is retained in the retracted position by theoverlapping engagement of the slotted lug 57 as shown in FIG. 11.Retraction of stop bolt 35 also closes the stop bolt sensor at switch73. Switch 73 acts as an interlock to prevent completion of theelectrical control circuit to motor control 63 at any time stop bolt 35is in its raised condition physically preventing pivotal movement of camplate 28.

When the actuator rod 38 has completed its downward movement, the draintimer 72 will have been set by cable 89 and the irrigation timer 87 willbe released for operation. The various elements on carriage 20 willremain in this operational condition through the period of time preseton the timer 87.

At the conclusion of operation of irrigation timer 87, valve 82 ismechanically reset to its lower position, which drains the area abovediaphragm 50 and initiates upward movement of actuator rod 38. Thisupward movement first closes the water discharge valve 15 by permittingball 19 to seat within the spherical enlargement 18, and then opens thewater seal about the exterior of the valve. Actuator rod 38 is returnedto its elevated position shown in FIG. 5, and carriage 20 remainsstationary. As the actuator rod 38 is raised, the irrigation timer 87 isreset for the next cycle, and the drain timer 72 is released. The draintimer 72 is preset to prevent closing of the electrical circuit to themotor control 63 during a time sufficient to assure gravity draining ofwater from the lateral pipeline 10.

At the conclusion of the cycle controlled by the drain timer 72, thecontacts shown at 72 in FIG. 14 close, completing a circuit to motorcontrol 63 through the closed stop bolt sensor switch 73. This initiatesoperation of the prime mover 13 and completes the cycling of theapparatus to its traveling mode.

As the carriage 20 begins to move, the cam plates 28, 30 swing abouttheir pivotal connections to clear riser 17 as shown in FIG. 7. When camplate 28 clears riser 17, it is returned to its neutral position shownin FIG. 8. This resets the cam follower 86 that controls the valve 82,which remains in its lower position. At the same time, the stop switch74 is closed just prior to opening of the stop bolt sensor switch 73.This timed relation of switches 74, 73 assures continuation of theelectrical circuit during the transition from the stationary mode to thetraveling mode and clearance of riser 17. After riser 17 has beencleared, the switch 73 is in its normally open condition. Switch 74 isin its normally closed condition. The drain timer contacts at 72 are intheir normally closed condition. The irrigation timer 87 is wound or setfor subsequent operation and the flange 36 at the outboard end of fluidconduit 16 is raised to clear the water discharge valves 15 along thesupply line 14. Carriage 20 will continue moving in unison with thelateral pipeline 10 until stop switch 74 is again activated to begin asubsequent cycle.

As described above, reversal or stopping of the carriage 20 isaccomplished by special tabs 71 which engage the lever 67 to operateswitch 66.

Having described my invention, I claim:
 1. A riser valve for anirrigation water supply line that is adapted to be releasably coupled toa pipeline having a coupler which includes: (1) lower riser engagingmembers having curved engaging surfaces; (2) an upper coupling fluidconduit having a flared terminal end; (3) an annular inner seal mountedat the flared terminal end; and (4) a valve actuating means, said riservalve comprising:an upright riser having exterior cylindrical wallsgenerated about a central riser axis; an exterior enlargementstationarily affixed at the upper end of the riser in open communicationwith the riser interior, said enlargement having (1) a lower exteriordiverging spherical surface complementary to the curved engagingsurfaces of the lower riser engaging members and adapted to be engagedthereby and an upper exterior converging spherical surface to be coupledto the fluid conduit with the annular inner seal interposed between theupper exterior converging spherical surface and the flared terminal endof the fluid conduit when the lower riser engaging members engage thelower exterior spherical surface; wherein the lower and upper sphericalsurfaces of the enlargement have an exterior radius greater than theexterior radius of the upright riser and wherein the lower exteriorspherical surface of the enlargement intersects the upright riser acrossa first plane perpendicular to the riser axis at the joinder between theenlargement and the riser; the upper end of the enlargement having anaperture formed through the upper exterior spherical surface thereof,said aperture being centered about the riser axis and intersecting theupper exterior spherical surface across a second plane perpendicular tosaid axis; and movable means mounted within the enlargement forselectively opening and closing said aperture in response to the valveactuating means.
 2. A riser valve as set out in claim 1 wherein theaperture formed at the upper end of the enlargement is circular;saidlast-named means comprising a spherical ball freely movable within theenlargement, the ball diameter being greater than the diameter of saidaperture.
 3. A riser valve for an irrigation water supply line that isadapted to be releasably coupled to a pipeline having a coupler having(1) lower clamping means; (2) upper clamping means; (3) drive means formoving one of the clamping means toward the other clamping means; and(4) valve actuating means, said riser valve comprising:an upright riseraffixed to the irrigation supply line and having a central riser axis;an exterior radial enlargement stationarily affixed at the upper end ofthe riser having (1) a lower spherical surface generated about a commoncenter of the central riser axis and adapted to be engaged by the lowerclamping means of the coupler and (2) an upper spherical surfacegenerated about a common center of the central riser axis and adapted tobe engaged by the upper clamping means for clamping the coupler to theriser valve when the drive means moves one of the clamping means towardthe other clamping means; an opening extending through the upper end ofthe enlargement; and movable means within the enlargement responsive tothe valve actuating means for opening and closing said opening.
 4. Ariser valve as set out in claim 3 wherein the opening has a circularconfiguration centered about said central axis.
 5. A riser valve as setout in claim 3 wherein the opening has a circular configuration centeredabout said central axis;said movable means comprising a spherical ballthat is capable of floating in water, the diameter of said opening beingless than the ball diameter.
 6. A riser valve as set out in claim 3wherein the opening is defined by an open circular rim at the upper endof said enlargement and centered about said central axis;said movablemeans comprising a spherical ball capable of floating in water, thediameter of said opening being less than the ball diameter; said ballhaving a resilient outer cover capable of sealing engagement at said rimwithout permanent deformation.